The tournament was unable to fully catch up from the fog delay that affected first-round play Thursday, but only 18 players were left on the course when it became too dark to play.
With winds becoming more of a factor at the Sea Island Resort, Kirk finished 36 holes at 8-under 132. That was one shot better than Kevin Chappell, Briny Baird, John Senden and 2012 U.S. Open winner Webb Simpson.
Simpson is already a winner in the 2014 PGA Tour season, which includes six tournaments that will be played prior to the new year.
Among those who were unable to finish the second round Friday, Seung-Yul Noh was best placed on the leaderboard. He was 5-under for the tournament with four holes to play.
Kirk played his round during the afternoon when the winds were at their strongest and he birdied five holes in a seven-hole stretch.
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